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Technological Diversities Observed in Bronze Objects of the Late Goryo Period - Case Study on the Bronze Bowls Excavated from the Burial Complex at Deobu-gol in Goyang - (고려 말 청동용기에 적용된 제작기술의 다양성 연구 - 고양 더부골 고분군 출토 청동용기를 중심으로 -)

  • Jeon, Ik Hwan;Lee, Jae Sung;Park, Jang Sik
    • Korean Journal of Heritage: History & Science
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    • v.46 no.1
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    • pp.208-227
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    • 2013
  • Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

Analysis of Vegetation-Environment Telationships of Main Wild Vegetables on Short-term Income Forest Products, in Korea (단기소득임산물 자생지 주요 산채류 식생과 환경의 상관관계 분석)

  • Kim, Hyoun-Sook;Lee, Sang-Myong;Lee, Joongku
    • Korean Journal of Environment and Ecology
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    • v.33 no.4
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    • pp.447-452
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    • 2019
  • This study was conducted in 2016-2017 to provide the basic ecological data needed to establish environmental conditions for the cultivation of wild vegetables. It used TWINSPAN to classify the vegetation structure of natural habitats of wild vegetable nationwide and DCCA ordination to analyze the correlation between the by community structure and environmental factors. We performed TWINSPAN on 100 taxa with high importance values in 91 plots of major habitats of wild vegetables. The vegetation was classified into Cirsium setidens and Synurus deltoides group, Ligularia fischeri and Hemerocallis fulva group, Adenophora divaricata var. manshurica group, Platycodon grandiflorum and Aster scaber group, Aralia elata and Pteridium aquilinum group, and Pimpinella brachycarpa and Osmunda japonica group communities. We then performed DCCA ordination of 11 communities classified by TWINSPAN and 11 environmental factors. The results showed that the altitude had the strongest correlation with the vegetation. The Cirsium setidens, Synurus deltoids, and Lifularia fischeri communities were distributed in areas with similar environmental factors such as high altitude, gentle slope, and nutrient. The Aralia elata and Osmunda japonica communities were distributed in the location environment with low altitude, pH, O.M, T-N, $Ca^{2+}$, and C.E.C. The Hemerocallis fulva community was distributed in the location environment with moderate northeastern and northwestern slope, low altitude and pH, and high $P_2O_5$, whereas the Adenophora divaricata var. manshurica community was distributed in the location environment with gentle southeastern and southwestern slope, high altitude and pH, and low $P_2O_5$, which was the opposite tendency of the location environment from Hemerocallis fulva community. The Platycodon grandiflorum community was distributed in the location environment with gentle southwestern slope, low altitude, pH, O.M, T-N, $P_2O_5$, $Ca^{2+}$, and C.E.C., and high $Mg^{2+}$. The Pteridium aquilinum community was distributed in the location environment with southwestern slope, low altitude, O.M, T-N, C.E.C, $P_2O_5$, $Ca^{2+}$, and $K^+$. The Aster scaber and Pimpinella brachycarpa communities were widely distributed in many plots with various location environments.

Fundamental Economic Feasibility Analysis on the Transition of Production Structure for a Forest Village in LAO PDR (라오스 산촌마을의 생산구조전환을 위한 투자 경제성 기초 분석)

  • Lee, Bohwe;Kim, Sebin;Lee, Joon-Woo;Rhee, Hakjun;Lee, Sangjin;Lee, Joong-goo;Baek, Woongi;Park, Bum-Jin;Koo, Seungmo
    • The Journal of the Korean Institute of Forest Recreation
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    • v.22 no.4
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    • pp.11-22
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    • 2018
  • This study analyzes the economic feasibility on the transition of production structure to increase income for a local forest village in Laos PDR. The study area was the Nongboua village in Sangthong district where the primary product is rice from rice paddy. Possible strategies were considered to increase the villagers' revenue, and Noni (Morinda citrifolia) was production in the short-term. We assumed that the project period was for 20 years for the analysis, and a total of 1,100 Noni tree was planted in 1 ha by $3m{\times}3m$ spacing. This study classified basic scenario one, scenario two, scenario three by the survival rate and purchase pirce of Noni. Generally Noni grows well. However, the seedlings' average survival rate (= production volume) was set up conservatively in this study to consider potential risks such as no production experience of Noni and tree disease. The scenario one assumed that the survival rate of Noni seedlings was 50% for 0-1 years, 60% for 0-2 years, and 70% for 3-20 years; the scenario two, 10% less, i.e., 40%, 50%, and 60%; and the scenario three, 10% less, i.e., 40%, 50%, 60% and purchase price 10% less, i.e., $0.29 to $0.26, respectively. Our analysis showed that all 3 scenarios resulted in economically-feasible IRR (internal rate of return) of 24.81%, 19.02%, and 16.30% of with a discounting rate of 10%. The B/C (benefit/cost) ratio for a unit area (1ha) was also analyzed for the three scenarios with a discounting rate of 10%, resutling in the B/C ratio of 1.71, 1.47, and 1.31. The study results showed that the Nongboua village would have a good opportunity to improve its low-income structure through planting and managing alternative crops such as Noni. Also the results can be used as useful decision-making information at a preliminary analysis level for planning other government and public investment projects for the Nonboua village.

Improving the Current Status and Cultural Value of Donguibogam Wanyoung Woodblocks (<동의보감(東醫寶鑑)> 완영(完營)책판의 현황과 문화재적 가치 제고(提高))

  • KIM, Hwaseon
    • Korean Journal of Heritage: History & Science
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    • v.55 no.2
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    • pp.50-64
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    • 2022
  • This thesis is a study on the woodblock of Donguibogam by Jeolla Gamyeong(Wanyoung Woodblock). It was registered as a tangible cultural property in Jeollabuk-do in 2005. The purpose of this article is to determine the current status and value of the Donguibogam Wanyoung Woodblock. Jeonju Hyanggyo's Wanyoung Woodblock was used to print books in Gamyeong, Jeolla Province. Currently, ten kinds of woodblocks are preserved. In 1987, a wooden bookshelf was installed and preserved in "Jangpangak" of Jeonju Hyanggyo. It is now preserved and managed at Chonbuk National University Museum. Among the ten woodblocks, the Wanyoung woodblock of Donguibogam is presumed to be a woodblock of a book printed by Jeolla Gamyeong in 1814. The value of Donguibogam has long been recognized domestically and internationally. Donguibogam, compiled in 1610, was first published in 1613 in the wood type of Gaeju Gapinja. Following its publication, its value was recognized not only in Joseon but also in China and Japan. In 2009, the first edition of Donguibogam was registered as a UNESCO World Heritage. Accordingly, Donguibogam has been recognized for various aspects, but little research has been conducted on the woodblocks that printed Donguibogam. Therefore, this paper analyzes the current status of the Wanyoung woodblock of Donguibogam, aiming to enhance its meaning and value. King Seonjo presented the ideals of public health care and preventive medicine when compiling Donguibogam, which was distributed according to his instructions. For this reason, the first edition of Donguibogam was registered as a UNESCO World Heritage. It can be said that the production of Donguibogam woodblocks was an important tool in realizing Joseon's ideals through national dissemination. Furthermore, the woodblock of Donguibogam represents the spirit of thinking about the people, going beyond the purpose of printing, and it was meaningful in the spread of medical knowledge among the people. In this article, I will examine the overall contents of the Wanyoung woodblock of Donguibogam to enhance its meaning and value. The results show that the Wanyoung woodblock of Donguibogam is meaningful in that it is almost the only one produced and stored by Gamyeong. Moreover, Wanyoung woodblocks are meaningful in that perfect editions could be preserved and disseminated for a long time, unlike other wood-type prints.